Energy systems need to be assessed in a holistic manner, looking at the efficiency of conversion and consumption, as well as the supply-side issues. The fact is that the conventional energy system is extremely inefficient. From primary energy through fuel production to the final energy service - be it warmth, light or motive power - we waste vast amounts of energy. Figure 1 shows how much energy is wasted in the UK system, for instance. Using British Government figures, it is possible to estimate that only around a third of the primary energy consumed in the UK is actually required to deliver the level of energy services received. Climate change will be extremely difficult and potentially expensive to tackle, if the systems that have delivered !his level of inefficiency survive far into the 21 st century. Policymakers need to apply seme lateral thinking if we are to reconcile economic progress with major reductions in greenhouse gases. HEAT IS THE KEY Whilst the political debate ever energy policy generally focuses on the fuel mix used to generale electricity, the main demand for nen-transport energy is for heating and cooling, which frequently does not involve electricity at all. lronically, of course, the conventional methods of power generation produce vast amounts of heat, which are then promptly lost in cooling towers or pumped into the sea. in Britain, the heat wasted in electricity generation is greater than the entire heat demand of the country. lf policy makers were to approach energy policy from !his angle, !hen CHP would immediately be central to their agenda. As heat is hard to stere or transport efficiently, the way mest electricity systems are set up with remote power stations far from population centres has made it difficult to make use of the waste heat. However, the prospect of micro CHP coming onto the market in 2003 suddenly offers the chance at last to turn that waste into usable energy and move the CHP industry out of its industrial and commercial niche and into the mass market. Estimates for the UK market, published by the Energy Saving Trust, show that ever half of the current nuclear capacity could be replaced by micro CHP by 2020. With virtually no increase in gas consumption as a result, this would be effectively converting waste heat into electricity. A 21ST CENTURY ENERGY SYSTEM The first micro-CHP units are being built, with Stirling engines or micro gas turbines. These will be largely heat-led and will not necessarily need to export much electricity, so will not require a very different type of electricity network. But the introduction of fuel cells is not far away, and in California, the Government is tendering for contracts to install fuel cells in seme public buildings. Fuel cells, with their higher electricity output, will have a more profound impact on electricity networks and energy policy. Wasıe heaı FIGURE 1. Nan-transport energy flow in the UK Space & waıer heallng lndusıry Ettlciency process ıosses Lighling & appliances Oıher The growth in micro CHP and from fuel cells in particular, will require a far more decentralized electricity system, with power being used and generated by potentially millions of sites. Net metering will become commonplace. Distribution networks will be about balancing two-way flows and active management, rather !han simply distributing a small number of high voltage sources to low voltage consumers. With !his will come further opportunities to improve on the efficiency of the system. lnformation technology and remote switching could enable seme loads, such as refrigeration or air conditioning, to be turneci down at times of peak demand or high price. Opportunities for energy service companies will increase with the growth in metering sophistication and local energy markets. Other technologies would benefit from a decentralized electricity system. Renewable energy is generally on a smaller scale than conventional fossil fuel. Seme technologies, such as photovoltaic roofs, will also be used on a micro scale, exporting power to the grid intermittently. Biomass CHP could also flourish in such a system, particularly in rural areas, where farmers in Europe are in need to routes to diversity. Looking further into the future, as the uptake of renewables and the contribution of CHP increases beyond 30% of electricity generation, seme form of energy storage technologies will be required to regulate the flow of intermittent renewables. There are a number of candidates for energy storage, including lnnogy's regenerative fuel celi technology, but in the long term the mest flexible option would be hydrogen, which can be used as a transport fuel, converted to electricity in a fuel celi or even mixed with natura! gas as a heating fuel. A growing consensus is emerging !hat the future of the energy industry is decentralized and small scale. There is a ECOGENERATION WORLO �47
RkJQdWJsaXNoZXIy MTcyMTY=